To simplify the process of making a display apparatus having a liquid crystal display (LCD) panel, a gate driver circuit for driving the display panel is integrated in the display panel and disposed within the periphery circuit area of the display panel. The gate driver circuit so integrated is known as a gate driver-on-array (GOA) structure. FIG. 1 shows a general layout of a display panel having a GOA structure. As shown in FIG. 1, the display panel 10 has a display area 40, a gate driver area 30 to provide gate-line signals to a plurality of gate lines G1, G2, . . . , Gn. An external circuit/connector 20 is used to provide clock signals and data or source signals to the display panel 10. The external circuit 20 has a timing control circuit 22 to generate timing control signals (CS). Based on the received control signals, a voltage level shifter 23 provides the clock signals (CK) and a start signal VST to the gate driver in the gate drive area 30. The external circuit 20 also has a source signal generator 24 to provide the source signals (S) to the display area 40 in response to the control signals CS.
Polarity inversion is often used in a liquid crystal display to reduce the deterioration of the liquid crystal layer. In a liquid crystal display where a liquid crystal layer is located between two substrates and an electric field is applied between the two substrates to control the orientation of the liquid crystal molecules in the layer. Typically the lower substrate includes gate lines, data lines and pixel electrodes, whereas the upper substrate includes a common electrode applied with a common voltage. The liquid crystal layer may be deteriorated if the electric field between the pixel electrodes and the common voltage maintains a fixed direction. Thus, the polarity of the voltage drop across the upper substrate and the lower substrate is periodically inverted.
In a display apparatus adopting the polarity inversion scheme, electrical coupling between the common electrode and various signals provided to the pixel electrodes may produce undesirable interference known as crosstalk.